This is a renewal grant application for an ongoing Program Project whose overall objectives have been the study of the chemistry, metabolism and molecular biology of connective tissues. The program is composed of 5 Subprojects and 2 Core Units. Project 1 will continue to investigate the mechanisms that regulate elastin gene expression and elastin fiber formation. Project 2 is a new Subproject; it will explore the mechanisms which regulate Type III collagen gene expression in cartilage. Project 3 will continue to investigate the nature and location of antigenic epitopes on Type IV collagen and examine structural and functional differences between laminins produced by normal and neoplastic cell lines. Project 4 will focus on studies which should explore the mechanisms of the nephritogenic immune response in interstitial nephritis. Project 5 will continue to utilize approaches that should help elucidate the molecular structure of genes which encode new collagen types. An Administrative Core Unit and a Core Laboratory Facility will supplement the research efforts.